benefit in kind · company · taxation
Company car benefit in kind in 2026: formula, reference CO2 and worked examples
The full 2026 company car benefit in kind formula in Belgium: reference CO2, age factor, legal minimum and worked examples for petrol, diesel and electric cars.
An employee or director who uses their company car privately is taxed on a benefit in kind (ATN). This flat-rate amount is added to their taxable remuneration — and it changes every year, because its parameters are indexed and revised. Here is how it works in full for 2026, with examples. One important point: benefit in kind only applies to vehicles provided by a company. A self-employed person trading as a sole trader has no benefit in kind on their own vehicle — see the tax advantages of an electric car for the self-employed.
The 2026 formula at a glance#
For a combustion-engine or hybrid vehicle:
annual benefit in kind = list price × age factor × CO2 percentage × 6/7
CO2 percentage = 5.5% + (vehicle CO2 − reference CO2) × 0.1%
capped between 4% and 18%
For a fully electric vehicle, the percentage is fixed at the 4% floor: benefit in kind = list price × age factor × 4% × 6/7.
In every case, the benefit in kind cannot fall below the legal minimum of €1,690 a year in 2026 (€1,650 in 2025, an amount indexed every year). The calculation is based on the list price of the vehicle when new, VAT included — even for a used car.
The 2026 reference CO2: the screw tightens#
The CO2 percentage is calculated against a reference emission level set each year. The lower that reference goes, the higher the benefit in kind on combustion-engine cars — for exactly the same vehicle.
| Income year | Petrol (g/km) | Diesel (g/km) |
|---|---|---|
| 2023 | 82 | 67 |
| 2024 | 78 | 65 |
| 2025 | 71 | 59 |
| 2026 | 70 | 58 |
The 2026 values (70 g/km for petrol, 58 g/km for diesel) are set by the Royal Decree of 17 December 2025 (Belgian Official Gazette of 24 December 2025). In practice, a petrol car emitting 120 g/km sees its percentage rise from 10.4% in 2025 to 10.5% in 2026: the benefit in kind goes up although the car has not changed.
The age factor: a month-by-month reduction#
The list price is reduced by 1% every two months from the 13th month after registration, down to a floor of 70%. The correct calculation averages the monthly factors over each year of ownership: a vehicle in its fourth year therefore sits at around 85.5% of its list price. After six years, the 70% floor is reached and the benefit in kind stabilises.
Three worked examples#
New petrol saloon — €35,000 list price, 120 g/km#
CO2 percentage: 5.5% + (120 − 70) × 0.1% = 10.5%. The benefit in kind is 35,000 × 100% × 10.5% × 6/7 = €3,150 a year, or €262.50 a month added to taxable remuneration. At a typical marginal rate of 45%, that means roughly €1,418 in tax a year for the driver. The same car in its fourth year (average age factor of about 85.5%) drops to some €2,693.
New diesel — €40,000 list price, 100 g/km#
CO2 percentage: 5.5% + (100 − 58) × 0.1% = 9.7%. Benefit in kind: 40,000 × 9.7% × 6/7, or about €3,326 a year. The lower diesel reference (58 g/km) penalises diesel at equal emissions.
New electric car — €38,000 list price#
38,000 × 4% × 6/7 = €1,303, below the legal floor: the benefit in kind is raised to the minimum of €1,690 a year, or about €141 a month. For a €55,000 model, the benefit in kind reaches €1,886 — still well below an equivalent combustion-engine car.
| Vehicle | List price | Percentage | Annual benefit in kind |
|---|---|---|---|
| Petrol, 120 g/km, new | €35,000 | 10.5% | €3,150 |
| Diesel, 100 g/km, new | €40,000 | 9.7% | €3,326 |
| Electric, new | €38,000 | 4% (minimum) | €1,690 (legal minimum) |
And for the employer: the disallowed expense#
The benefit in kind does not only cost the employee. For the employer, part of the vehicle-related benefit is treated as a disallowed expense: it is added back to the company's taxable base and taxed at corporate income tax rates (25%, or 20% for SMEs on the first band of profit). The exact amount of this disallowed expense depends on the situation, notably on whether the company pays for fuel — a point to check with your accountant. On top of that comes the NSSO CO2 solidarity contribution, due every month for every company car.
How to reduce benefit in kind, legally#
The formula points to three levers: choose electric (4% instead of up to 18%), aim for a reasonable list price (every €10,000 of options is paid for every year), and take the vehicle's age into account (the 70% floor is reached after six years). Benefit in kind is only one cost among many: deductibility depending on the order date and the financing method weigh at least as much. In AutoCalcul, benefit in kind is never roughly estimated: it is calculated from the statutory formula, year by year, with the monthly granularity of the age factor — and the comparison tool puts two vehicles side by side, benefit in kind included.
Tax rules change — check the legislation in force.